2 BULLETIN" 681^ U. S. DEPARTMENT OP AGRICULTURE. 



In June, 1913, an explosion in a feed-grinding plant in Buffalo, 

 N. Y., caused the death of 33 men, injured more than 70 employees, 

 and damaged a great deal of grain and property. Shortly afterwards 

 the Bureau of Chemistry began its work in connection with dust 

 explosions in grain mills, elevators, and industrial plants. During 

 the period in which this study has been carried on a large number of 

 disastrous dust explosions, in which many lives have been lost, 

 large quantities of grain and food products destroyed, and much 

 property damaged, have occurred in grain elevators, feed, cereal, and 

 flour mills, starch factories, sugar refineries, and other industrial 

 plants which handle grain. Several definite causes for these explo- 

 sions have, been established, and effective preventive methods have 

 been developed and tested. At present the United States Depart- 

 ment of Agriculture is conducting a special war-emergency campaign 

 for the prevention of dust explosions and fires. Representatives of 

 the department are rendering direct assistance to the millers and 

 grain men of the country in installing devices for preventmg ex- 

 plosions and in showing them how to remedy dangerous conditions. 



The grain-dust explosion work, as conducted by the Bureau of 

 Chemistry, falls into two general classes: 



XX) Du'st explosions which occur in grain mills, elevators, and 

 industrial plants during the handling and milling of grains and the 

 manufacture of food products. 



(2) Dust explosions which occur in thrashing machines during the 

 operations in the harvest fields. 



MILL AND ELEVATOR EXPLOSIONS. 



As soon as joossible after the occurrence of an explosion in a mill or 

 elevator, the field engineers of the bureau investigate carefully the 

 conditions under which the explosion originated and assist the 

 company to devise and install some means for preventing any more 

 such explosions. During the course of these field investigations it 

 has become apparent that one of the causes for a large number of 

 dust explosions and fires in the cereal and feed mills, particularly in 

 the feed-grinding departments, is the ignition of the dust on the- 

 interior of the grinding machine during operation. In many 

 instances the evidence indicated that the explosion and fire originated 

 within the machine, usually in the attrition type of mill. As they were 

 believed to have been caused by sparks from foreign particles or me- 

 tallic substances entering with the grain, the bureau emphasized the 

 necessity for taking steps to remove these materials from the mill 

 stream before it entered the grinding machines.^ 



1 Preliminary Report on the Explosibility of Grain Dusts, Cooperative Investigatirn by Millers Com- 

 mittee, Bnflalo, N . Y., under the direction of Dr. George A. Hulett, chief chemist, Bureau of Mines, U.S. 

 Department of the Interior, by David J. Price, engineer in charge, and Harcld H. Brown, assistant 

 chemist, Graih-Dust Explosion Investigations, Bureau of Chemistry, U. S. Department of Agriculture 

 Copies no longer obtainable. 



